NORTH-AMERICAN EXPERIENCE WITH THE PERMA-FLOW PROSTHETIC CORONARY GRAFT

Background. The Perma-Flow prosthetic coronary graft is a 5-mm polytet rafluoroethylene tube into which is incorporated a Venturi flow restri ctor. An aorto-superior vena caval fistula is created and coronary ana stomoses are constructed proximal to the resistor in side-to-side fash ion, where arterial pressure is maintained. From November 1992 through December 1995, eight investigational centers in North America have im planted this graft in 40 patients with inadequate autologous alternati ves. Methods. Patients were selected for inclusion in this study if co ronary artery bypass grafting was required and adequate autologous con duit to complete revascularization was not available. Operative data w ere completed by the implantating surgeon and referred to a central ce nter, the Minneapolis Heart Institute, for correlation. Follow-up was conducted by data coordinators at each institution, and follow-up data were obtained directly from these coordinators for inclusion in the s tudy. Results. Patient age ranged from 53 to 82 years, and 15 patients were undergoing reoperations (38%). On each Perma-Flow graft one to f our coronary side-to-side anastomoses were constructed. In addition, l eft internal mammary artery (n = 26), greater saphenous vein (8), righ t internal mammary artery (4), and gastroepiploic artery (4) were used to complete revascularization. Aortic (2) or mitral valve replacement (1) was also carried out. There were seven operative deaths (18%) and two late deaths (4 and 6 months). After 1 to 37 months (mean, 13 +/- 9 months) of follow-up, 29 of 31 surviving patients are asymptomatic. Echocardiographic heart size has not increased from the postoperative value, indicating limited volume load has not affected heart size. Pro tocol catheterization (n = 32) in 28 patients 1 week to 1 year postope ratively revealed 7 of 73 studied coronary anastomoses (9.5%) and two distal extensions and resistors were occluded (7%). In 1 patient durin g sternal debridement at 1 year, no flow was found in the graft. Concl usions. The Perma-Flow graft is a useful adjunct to complete revascula rization in patients with deficient autologous conduit.